Electric multipolar rotatable switch with helical rotor drive

ABSTRACT

An electrical multipolar switch having several rotary angular positions for providing the required connections in an electrical equipment by means of stationary plugs and movable strips, wherein the improvement consists in the provision of independent contact strips set into a base made from insulating and resilient material without any connections between each other inside of said base, said strips being formed each one endwise with a top bent at right angles and frictionally engageable with stationary plugs distributed angularly in several azimuthal directions about the switch axis.

United States Patent 1 1111 3,867,601 Lipschutz Feb. 18, 1975 [54] ELECTRIC MULTIPOLAR ROTA IABLE 3,488,458 1/1970 Tolman .1 200/16 1) SWITCH WITH HELICAL ROTOR DRIVE Inventor: Paul Lipschutz, Croissy-Sur-Seine,

France Assignees: Societe dExploitation des Brevets l\l e i n a i l leuilly S/ Seine, France FOREIGN PATENTS OR APPLICATIONS Primary Examiner-Robert K. Schaefer [22] Filed: Oct. 17, 1973 Assistant ExaminerGerald P. Tolin [21] Appl No 407 387 Attorney, Agent, or Firm-Nolte and Nolte [30] Foreign Application Priority Data 57 ABSTRACT Oct. 20, 1972 France 72.37253 An electncal multlpolar switch having several rotary 52 us. c1 200/158, 200/16 D, 200/18, angular Positions for providing the required Connec- 20O/252 tions in an electrical equipment by means of stationary 51 1m.c1. HOlh 3/40 Plugs and movable Strips, wherein the improvement 5 Field f Search 200 3 16 C, 161) 7 R consists in the provision of independent contact strips 00 13 5 4 R 5 B 5 D, 166 set into a base made from insulating and resilient ma- 333/143 148, 202 terial without any connections between each'other inside of said base, said strips being formed each one 5 References Cited endwise with a top bent at right angles and frictionally UNITED STATES PATENTS engageable with stationary plugs distributed angularly in several azimuthal directions about the switch axis. 3,246,l0l 4/1966 Caputo 200/16 B 1 5 Claims, 5 Drawing Figures 11 n E. f

J L- l2 17 7 I 8 i 'l O 1 1 2 9 3 l 4 ELECTRIC MULTIPOLAR ROTATABLE SWITCH WITH HELICAL ROTOR DRIVE The present invention relates to multipolar or multiple throw electric switches or the like. There is known a large number of multipolar electric switches designed and made for various applications and uses.

As the general trend in electrical installations or plants is towards miniaturization this way of development is however limited by safety and reliability requirements which prescribe contact surfaces and spacing distances between electrodes of'opposite polarities consistent with the selected insulating materials and and air gaps.

Generally under such circumstances the switches designed for electrical equipments or outfits, in particular those of automotive vehicles comply with the following requirements:

small size or bulk low cost price reliability balanced pressure between the elements, members,

devices or parts forming the various electrical circuits.

When several different connections or junctions between circuits depending upon one another have to be made through a rotary motion it is practically impossible owing to the above-stated requirements to achieve accurate angular positions without any interference.

The electric switch which is the subject matter of the present invention is a solution of the difficult problem of avoiding interferences between angular positions.

Another object of the invention is to provide perfect contacts between stationary and movable electrodes pressed or pushed against each other by a resilient device for some positions and with a suitable pressure.

A further object of the invention is to withdraw such resilient means from the flow or passage of electrical current therethrough which would cause in course of time through heating up (JOULE effect) combined with mechanical stresses or strains, a decay of the original elasticity or resiliency which should remain constant since it is a requirement for achieving a good operation.

Still another object of the invention is to periodically clean the surfaces of the contacts which may be impaired or spolied by the flow or passage of electric current therethrough or by sparks, in particular through shifting or displacing the small areas where contacts are made.

The switch according to the invention enables to attain these objects on the one hand by the use of new materials and on the other hand by conversion of rotary movement into linear movement thereby removing any kinematical constraints due to the purely angular displacement.

It should be noted that it is of course possible to use both rotary and translatory motions as this may become necessary in most industrial achievements.

A form of embodiment will now be described by way of merely illustrative and non-limiting example with reference to the Figures of the accompanying drawings wherein:

FIG. 1 is a view in vertical diametral section of the switch assembly taken upon the line I-I in FIG.

FIG. 2 is a perspective view showing the position of a contact strip or like lamination prior to its being mounted in its contactor appliance, its position being inclined outwards with respect to its resilient support or like holding or carrying member;

FIG. 3 is a perspective view also showing after having been mounted an operative position of a strip or like lamination providing connection between two plugs, the contact pressure being provided by the stress ofthe resilient supporting member;

FIG. 4 is a perspective view showing the position of the same contact strip of lamination when the plugs are offset or shifted with respect to each other for instance in their distance and orientation relative to the general axis or centre line; and

FIG. 5 is a cross-section of the switch taken upon the plaen VV in FIG. I.

It appears from FIG. I that the switch consists of a body 1 made from insulating material. The bore of this body is formed with a helical ramp or like groove 2 the outline of which is shown in dotted lines at the bottom portion of FIG. 1. A driving member 4 is positioned inside of this bore. It is rotatable by an operating rod or shaft 5 formed with a flattened or half flat drive portion 6; a feather or snug spigot 3, provided on said drive member, is movable inside of the groove 2 whereby any rotary motions are converted into combined rotary and translator or linear motions.

In other words when the shaft 5 is rotated, the drive member 4 is displaced axially under the action of the groove 2.

The axial travel is transmitted to the element 16 which is so to speak capping the inner end of drive member 4. The element 16 cannot rotate as it is provided with a feather or like snug spigot 8 which is slidable within a groove 7 extending in parallel relation to the axis of rotation.

A circlip or like snap-keeper ring or retaining ring 10 prevents the drive member 4 from leaving the element 16 in the axial direction. The rotary displacement of the shaft 5 results therefore in a movement in either direction in parallel relation to the axis of the element 16.

If required and as shown a central spring 17 may be used as an antibacklash adjusting device for taking up the slack, clearance or wear.

The element 16 accommodates an essential part which is a resilient insulating member 11 wherein are set contact strips or like laminations 12 which have the shape shown in FIGS. 2, 3 and 4 and which are clamped, seated or force-fitted within this elastic part.

In FIG. 1 has been shown in dashed lines the end position which may assume the strips 12 which are bent substantially or nearly at right angles at their ends and which in their contact position are frictionally engaging plugs 13, 13', made of electrically conducting material.

Thus the rotation of the drive member 4 results in a movement of the noses or bent ends or tips of the strips 12 in parallel relation to the axis, which in the embodiment shown have the shape of two half circles. These tips or bent ends of the strips 12 are engageable in contacting relationship with the lugs l3, 13'.

When the switch is turned back to the zero position under the action of the drive member and possibly of the spring 17, the tips of the strips 12 leave the surface of the small plates or laminations 13, 13' forming the plugs and the contact is broken. 1

The cross-sectional view from above 5 shows an examplary distribution of the strips 12 about the axis of the switch to thereby provide several contacts between the plugs 13, 13, etc.

It is possible to space more or less both plugs 13 and 13' from the centre, the inherent elasticity of the slightly outward sloping contact strips 12 adding to the original elasticity of the part 11 wherein the strips 12 are set or force-fitted with an initial prestress; since these contact strips may be perfectly stiff or rigid, it is possible to make them from materials exhibiting an excellent conductivity and the fact of not making them resilient enables to give them the cross-sectional area required for the flow of electrical current therethrough.

The elastic part 11 is firmly held when being mounted within the cup 16 and accordingly it may be manufactured together with this shell member 16 at the v same time into an assembly.

The operation of the switch may be understood from the previous explanations; rotary motions imparted to the drive member 4 through its actuating shaft 5 cause the strips 12 to slidingly move into contact with the plugs 13, 13, etc. in the order or sequence desired and at the required time.

The different rotary positions may correspond to positions differing in height since the plugs are not compulsorily made according to a configuration in parallel relation to the axis and since a same strip 12 may make contact between plugs located in different azimuthul positions.

Of course, the invention is by no means limited to the form of embodiment described and illustrated, which has been given by way of example only. In particular, it comprises all the means constituing technical equivalents to the means described as well as their combinations, should the latter be carried out according to the gist of the invention.

What is claimed is:

1. An electrical multipolar switch having several rotary angular positions for providing the required connections in an electrical equipment, including a stator provided with stationary plugs angularly distributed about a switch axis and a base axially movable in said stator, made from insulating material and strips set into said base without any connection between each other inside of said base. said strips being engageable with said stationary plugs, wherein the improvement comprises a rotor provided with means engaging with means provided in the stator for imparting to said rotor a helical movement upon rotation thereof and in that said base is axially aligned with and carried by said rotor and mounted non-rotatably in said stator, whereby the rotary motion of said rotor is converted in a translatory motion of said base and said contact strips.

2. A switch according to claim 1 wherein said stator is provided with an axial bore formed with an helical groove and with a longitudinal groove extending in parallel relation to the axis of rotation of the switch, said rotor rotatably mounted in said bore of said stator and provided with a radially outward projecting feather engaging said helical groove, said rotor carrying a nonrotatable cup-like member formed with a radially outward projecting spigot slidably engaging said longitudinal groove of said stator, whereby the rotary motion of said rotor is converted into a translatory motion of said cup-like member and said base is held firmly within said cup-like member.

3. A switch according to claim 2, wherein said rotor carries a resilient base member into which said movable strips are set and said movable strips are provided with T-shaped bent tips each having two outwardly pro jecting contact areas arranged to provide an electrical contact between said stationary plugs when contacting same.

4. A switch according to claim 3, comprising cleaning means for the contacting areas where electrical current is flowing therethrough, whereby the combined driving of said rotor according to a rotory and a translatory motion results in a linear displacement of said contact strips and successive frictional rubbing engagment thereof with said stationary plugs to achieve the cleaning of said areas.

5. Switch according to claim 4, wherein said movable strips are made from non-resilient material.

l l l 4 

1. An electrical multipolar switch having several rotary angular positions for providing the required connections in an electrical equipment, including a stator provided with stationary plugs angularly distributed about a switch axis and a base axially movable in said stator, made from insulating material and strips set into said base without any connection between each other inside of said base, said strips being engageable with said stationary plugs, wherein the improvement comprises a rotor provided with means engaging with means provided in the stator for imparting to said rotor a helical movement upon rotation thereof and in that said base is axially aligned with and carried by said rotor and mounted non-rotatably in said stator, whereby the rotary motion of said rotor is converted in a translatory motion of said base and said contact strips.
 2. A switch according to claim 1 wherein said stator is provided with an axial bore formed with an helical groove and with a longitudinal groove extending in parallel relation to the axis of rotation of the switch, said rotor rotatably mounted in said bore of said stator and provided with a radially outward projecting feather engaging said helical groove, said rotor carrying a non-rotatable cup-like member formed with a radially outward projecting spigot slidably engaging said longitudinal groove of said stator, whereby the rotary motion of said rotor is converted into a translatory motion of said cup-like member and said base is held firmly within said cup-like member.
 3. A switch according to claim 2, wherein said rotor carries a resilient base member into which said movable strips are set and said movable strips are provided with T-shaped bent tips each having two outwardly projecting contact areas arranged to provide an electrical contact between said stationary plugs when contacting same.
 4. A switch according to claim 3, comprising cleaning means for the contacting areas where electrical current is flowing therethrough, whereby the combined driving of said rotor according to a rotory and a translatory motion results in a linear displacement of said contact strips and successive frictional rubbing engagment thereof with said stationary plugs to achieve the cleaning of said areas.
 5. Switch according to claim 4, wherein said movable strips are made from non-resilient material. 